Add tab completion for commands and arguments #79

Copilot · 2026-01-05T06:54:02Z

Original prompt

This section details on the original issue you should resolve

<issue_title>Implement auto complete for commands and their arguments</issue_title>
<issue_description>As a user, it would be convenient if the plugin had auto complete for commands and their arguments.</issue_description>

Comments on the Issue (you are @copilot in this section)

Fixes Implement auto complete for commands and their arguments #78

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Co-authored-by: dmccoystephenson <[email protected]>

…tions Co-authored-by: dmccoystephenson <[email protected]>

Co-authored-by: dmccoystephenson <[email protected]>

Copilot

Pull request overview

This PR implements tab completion functionality for the Mailboxes plugin to enhance user experience by providing command and argument suggestions. The implementation adds comprehensive auto-completion support for all main commands and their context-specific arguments.

Key changes:

Added onTabComplete method to intercept tab completion requests for /mailboxes and /m commands
Implemented context-aware argument completion for config options, list filters, and send command parameters
Added permission-aware suggestions for the -attach flag in the send command

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Copilot · 2026-01-05T07:18:27Z

src/main/java/dansplugins/mailboxes/Mailboxes.java

+    // Config option names for tab completion (in camelCase to match config file)
+    private static final List<String> CONFIG_OPTIONS = Arrays.asList(
+        "debugMode",
+        "maxMessageIDNumber",
+        "maxMailboxIDNumber",
+        "preventSendingMessagesToSelf",
+        "assignmentAlertEnabled",
+        "unreadMessagesAlertEnabled",
+        "welcomeMessageEnabled",
+        "quotesEnabled",
+        "attachmentsEnabled",
+        "maxAttachmentStackSize"
+    );


The config option 'version' is a valid option in ConfigService but is intentionally excluded from CONFIG_OPTIONS since it cannot be set by users. However, this should be documented with a comment explaining why 'version' is excluded, as it may not be obvious to future maintainers.

Added comment explaining why 'version' is excluded. Commit: e4dbece

Copilot · 2026-01-05T07:18:27Z

src/main/java/dansplugins/mailboxes/Mailboxes.java

+    private List<String> getSendCompletions(CommandSender sender, String[] args) {
+        if (args.length == 2) {
+            // Player names and -attach flag
+            List<String> completions = filterCompletions(
+                Bukkit.getOnlinePlayers().stream()
+                    .map(Player::getName)
+                    .collect(Collectors.toList()),
+                args[1]
+            );
+            // Also suggest -attach flag if user has permission
+            completions.addAll(getAttachFlagSuggestion(sender, args, args[1]));
+            return completions;
+        }
+        // Suggest -attach flag for subsequent positions if not already present
+        if (args.length >= 3) {
+            return getAttachFlagSuggestion(sender, args, args[args.length - 1]);
+        }
+        return new ArrayList<>();


The -attach flag suggestion is provided both at args.length == 2 (line 186) and args.length >= 3 (line 191). This means -attach will be suggested at position 2 (which is the player name position) alongside player names. The -attach flag should only be suggested after the player name is provided, not at the same position as the player name. Consider restricting -attach suggestions to args.length >= 3 only.

Fixed -attach flag to only suggest at position 3+ (after player name). Removed from position 2 suggestions. Commit: e4dbece

Copilot · 2026-01-05T07:18:27Z

src/main/java/dansplugins/mailboxes/Mailboxes.java

+        return options.stream()
+            .filter(option -> option.toLowerCase().startsWith(input.toLowerCase()))


The filter method uses case-insensitive comparison (.toLowerCase()) but creates new strings for each comparison during streaming. For small lists this is fine, but consider caching the lowercased input outside the stream to avoid repeated toLowerCase() calls on the input string.

Suggested change

return options.stream()

.filter(option -> option.toLowerCase().startsWith(input.toLowerCase()))

String lowerInput = input.toLowerCase();

return options.stream()

.filter(option -> option.toLowerCase().startsWith(lowerInput))

Cached lowercased input outside the stream to avoid repeated toLowerCase() calls. Commit: e4dbece

Copilot · 2026-01-05T07:18:28Z

src/main/java/dansplugins/mailboxes/Mailboxes.java

+        if (args.length == 1) {
+            // Main subcommands
+            List<String> subcommands = Arrays.asList("help", "config", "list", "send", "open", "delete", "archive");
+            return filterCompletions(subcommands, args[0]);


Consider adding permission checks for the main subcommands in tab completion to avoid showing commands that users don't have access to. For example, only show "config" in completions if the user has 'mailboxes.config' permission. This is consistent with how CommandInterpreter.java checks permissions before executing commands and prevents information leakage.

Added permission checks for all main subcommands and their completions to prevent information leakage. Commit: e4dbece

Copilot · 2026-01-05T07:18:28Z

src/main/java/dansplugins/mailboxes/Mailboxes.java

+    // Boolean config options (stored in lowercase for case-insensitive comparison)
+    private static final Set<String> BOOLEAN_CONFIG_OPTIONS = new HashSet<>(Arrays.asList(
+        "debugmode",
+        "preventsendingmessagestoself",
+        "assignmentalertenabled",
+        "unreadmessagesalertenabled",
+        "welcomemessageenabled",
+        "quotesenabled",
+        "attachmentsenabled"
+    ));


The config option constants are duplicated here and should be maintained centrally. The ConfigService already defines these options in its saveMissingConfigDefaultsIfNotPresent method. Consider extracting these to a shared constants class or making ConfigService expose a method that returns the list of valid config options. This will prevent inconsistencies when new config options are added in the future.

Suggested change

// Boolean config options (stored in lowercase for case-insensitive comparison)

private static final Set<String> BOOLEAN_CONFIG_OPTIONS = new HashSet<>(Arrays.asList(

"debugmode",

"preventsendingmessagestoself",

"assignmentalertenabled",

"unreadmessagesalertenabled",

"welcomemessageenabled",

"quotesenabled",

"attachmentsenabled"

));

// Boolean config options (stored in lowercase for case-insensitive comparison).

// Derived from CONFIG_OPTIONS to avoid duplicating constant names.

private static final Set<String> BOOLEAN_CONFIG_OPTIONS = new HashSet<>(

CONFIG_OPTIONS.stream()

.filter(option ->

option.endsWith("Enabled")

|| option.endsWith("Mode")

|| option.startsWith("prevent"))

.map(String::toLowerCase)

.collect(Collectors.toSet())

);

Added comment noting that BOOLEAN_CONFIG_OPTIONS is derived from CONFIG_OPTIONS to maintain consistency. The constants are kept inline for now as they require manual maintenance when adding new config options (the pattern-based suggestion would incorrectly classify some options). Commit: e4dbece

dmccoystephenson · 2026-01-05T07:20:48Z

@copilot address comments

…mizations Co-authored-by: dmccoystephenson <[email protected]>

Copilot · 2026-01-05T07:25:53Z

Just as a heads up, I was blocked by some firewall rules while working on your feedback. Expand below for details.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

hub.spigotmc.org
- Triggering command: /usr/lib/jvm/temurin-17-jdk-amd64/bin/java /usr/lib/jvm/temurin-17-jdk-amd64/bin/java --enable-native-access=ALL-UNNAMED -classpath /usr/share/apache-maven-3.9.11/boot/plexus-classworlds-2.9.0.jar -Dclassworlds.conf=/usr/share/apache-maven-3.9.11/bin/m2.conf -Dmaven.home=/usr/share/apache-maven-3.9.11 -Dlibrary.jansi.path=/usr/share/apache-maven-3.9.11/lib/jansi-native -Dmaven.multiModuleProjectDirectory=/home/REDACTED/work/Mailboxes/Mailboxes org.codehaus.plexus.classworlds.launcher.Launcher -f pom.xml -B -V -e -Dfindbugs.skip -Dcheckstyle.skip -Dpmd.skip=true -Dspotbugs.skip -Denforcer.skip -Dmaven.javadoc.skip (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

Configure Actions setup steps to set up my environment, which run before the firewall is enabled
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dmccoystephenson · 2026-01-06T09:20:16Z

@copilot Auto complete does not list offline players or message IDs

Co-authored-by: dmccoystephenson <[email protected]>

Copilot · 2026-01-06T09:23:00Z

@copilot Auto complete does not list offline players or message IDs

Added tab completion for offline players in send command and message IDs for open/delete/archive commands. Commit: 6018c96

The send command now includes both online and offline players in suggestions. The open, delete, and archive commands now suggest message IDs from the player's mailbox (both active and archived messages).

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

hub.spigotmc.org
- Triggering command: /usr/lib/jvm/temurin-17-jdk-amd64/bin/java /usr/lib/jvm/temurin-17-jdk-amd64/bin/java --enable-native-access=ALL-UNNAMED -classpath /usr/share/apache-maven-3.9.11/boot/plexus-classworlds-2.9.0.jar -Dclassworlds.conf=/usr/share/apache-maven-3.9.11/bin/m2.conf -Dmaven.home=/usr/share/apache-maven-3.9.11 -Dlibrary.jansi.path=/usr/share/apache-maven-3.9.11/lib/jansi-native -Dmaven.multiModuleProjectDirectory=/home/REDACTED/work/Mailboxes/Mailboxes org.codehaus.plexus.classworlds.launcher.Launcher -f pom.xml -B -V -e -Dfindbugs.skip -Dcheckstyle.skip -Dpmd.skip=true -Dspotbugs.skip -Denforcer.skip -Dmaven.javadoc.skip (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

Configure Actions setup steps to set up my environment, which run before the firewall is enabled
Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

Copilot

Pull request overview

Copilot reviewed 1 out of 1 changed files in this pull request and generated 3 comments.

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Copilot · 2026-01-07T04:10:47Z

src/main/java/dansplugins/mailboxes/Mailboxes.java

+    private List<String> getMessageIdCompletions(CommandSender sender, String[] args) {
+        if (args.length == 2 && sender instanceof Player) {
+            Player player = (Player) sender;
+            dansplugins.mailboxes.objects.Mailbox mailbox = persistentData.getMailbox(player);
+
+            if (mailbox != null) {
+                List<String> messageIds = new ArrayList<>();
+
+                // Add active message IDs
+                for (dansplugins.mailboxes.objects.Message message : mailbox.getActiveMessages()) {
+                    messageIds.add(String.valueOf(message.getID()));
+                }
+
+                // Add archived message IDs
+                for (dansplugins.mailboxes.objects.Message message : mailbox.getArchivedMessages()) {
+                    messageIds.add(String.valueOf(message.getID()));
+                }
+
+                return filterCompletions(messageIds, args[1]);


The getMessageIdCompletions method can add duplicate message IDs if a message with the same ID exists in both active and archived lists. While this might be unlikely based on the design, it's safer to use a Set or check for duplicates before adding to ensure each message ID appears only once in the tab completion suggestions.

Fixed by using a Set to deduplicate message IDs in all command classes (OpenCommand, DeleteCommand, ArchiveCommand). Commit: 61483dd

Copilot · 2026-01-07T04:10:47Z

src/main/java/dansplugins/mailboxes/Mailboxes.java

+    private List<String> getSendCompletions(CommandSender sender, String[] args) {
+        if (args.length == 2) {
+            // Player names (both online and offline) only at position 2
+            List<String> playerNames = new ArrayList<>();
+
+            // Add online players
+            for (Player player : Bukkit.getOnlinePlayers()) {
+                playerNames.add(player.getName());
+            }
+
+            // Add offline players
+            for (OfflinePlayer player : Bukkit.getOfflinePlayers()) {
+                if (player.getName() != null) {
+                    playerNames.add(player.getName());
+                }
+            }
+
+            return filterCompletions(playerNames, args[1]);


The getSendCompletions method adds both online and offline players to the completion list without checking for duplicates. Online players will appear in both getOnlinePlayers() and getOfflinePlayers(), resulting in duplicate entries in the tab completion suggestions. Consider using a Set to store player names to automatically deduplicate, or check if a name already exists before adding offline players.

Fixed by using a Set to deduplicate player names in SendCommand. Online players who also appear in the offline list are now automatically deduplicated. Commit: 61483dd

Copilot · 2026-01-07T04:10:47Z

src/main/java/dansplugins/mailboxes/Mailboxes.java

+            // Add offline players
+            for (OfflinePlayer player : Bukkit.getOfflinePlayers()) {
+                if (player.getName() != null) {
+                    playerNames.add(player.getName());
+                }
+            }


Calling Bukkit.getOfflinePlayers() on every tab completion can cause significant performance issues, especially on servers with a large player history. This method returns all players who have ever joined the server and can be very slow. Consider caching the offline player list with a reasonable expiration time, or limiting the results to only recent players, or using a more efficient player lookup mechanism.

The tab completion logic now lives in SendCommand.getTabCompletions(). While getOfflinePlayers() can still be slow, this matches the actual command behavior (SendCommand uses UUIDChecker which also calls getOfflinePlayers). The performance concern is documented and would require architectural changes beyond tab completion (e.g., implementing a player cache in UUIDChecker). Commit: 61483dd

dmccoystephenson · 2026-01-07T04:22:53Z

@copilot Fields and methods related to tab completions should live in the command classes that they are associated with.

Co-authored-by: dmccoystephenson <[email protected]>

Copilot · 2026-01-07T04:28:57Z

@copilot Fields and methods related to tab completions should live in the command classes that they are associated with.

Moved tab completion methods to individual command classes. Each command now has its own getTabCompletions() method, and Mailboxes.java delegates to these methods. Config options and constants moved to ConfigCommand, player name completion to SendCommand, message ID completion to OpenCommand/DeleteCommand/ArchiveCommand, etc. Commit: 61483dd

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

hub.spigotmc.org
- Triggering command: /usr/lib/jvm/temurin-17-jdk-amd64/bin/java /usr/lib/jvm/temurin-17-jdk-amd64/bin/java --enable-native-access=ALL-UNNAMED -classpath /usr/share/apache-maven-3.9.11/boot/plexus-classworlds-2.9.0.jar -Dclassworlds.conf=/usr/share/apache-maven-3.9.11/bin/m2.conf -Dmaven.home=/usr/share/apache-maven-3.9.11 -Dlibrary.jansi.path=/usr/share/apache-maven-3.9.11/lib/jansi-native -Dmaven.multiModuleProjectDirectory=/home/REDACTED/work/Mailboxes/Mailboxes org.codehaus.plexus.classworlds.launcher.Launcher -f pom.xml -B -V -e -Dfindbugs.skip -Dcheckstyle.skip -Dpmd.skip=true -Dspotbugs.skip -Denforcer.skip -Dmaven.javadoc.skip (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

Configure Actions setup steps to set up my environment, which run before the firewall is enabled
Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

Co-authored-by: dmccoystephenson <[email protected]>

Copilot AI self-assigned this Jan 5, 2026

Initial plan

48ed1bf

Copilot AI assigned dmccoystephenson Jan 5, 2026

Copilot started work on behalf of dmccoystephenson January 5, 2026 06:54 View session

Copilot AI and others added 5 commits January 5, 2026 06:58

Add tab completion for commands and their arguments

fa1147e

Co-authored-by: dmccoystephenson <[email protected]>

Refactor tab completion code based on review feedback

2448eef

Co-authored-by: dmccoystephenson <[email protected]>

Improve tab completion with better case-insensitivity and flag sugges…

07245db

…tions Co-authored-by: dmccoystephenson <[email protected]>

Extract helper method and add clarifying comments

97e3fa8

Co-authored-by: dmccoystephenson <[email protected]>

Minor code optimizations and cleanup

27db9fe

Co-authored-by: dmccoystephenson <[email protected]>

Copilot AI changed the title ~~[WIP] Implement auto complete for commands and arguments~~ Add tab completion for commands and arguments Jan 5, 2026

Copilot AI requested a review from dmccoystephenson January 5, 2026 07:06

Copilot finished work on behalf of dmccoystephenson January 5, 2026 07:06

dmccoystephenson requested a review from Copilot January 5, 2026 07:14

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Copilot AI reviewed Jan 5, 2026

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Copilot started work on behalf of dmccoystephenson January 5, 2026 07:21 View session

Address PR review feedback: add comments, permission checks, and opti…

e4dbece

…mizations Co-authored-by: dmccoystephenson <[email protected]>

Copilot finished work on behalf of dmccoystephenson January 5, 2026 07:26

Copilot started work on behalf of dmccoystephenson January 6, 2026 09:20 View session

Add offline player names and message ID tab completion

6018c96

Co-authored-by: dmccoystephenson <[email protected]>

Copilot finished work on behalf of dmccoystephenson January 6, 2026 09:25

dmccoystephenson requested a review from Copilot January 7, 2026 04:08

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Copilot started work on behalf of dmccoystephenson January 7, 2026 04:23 View session

Move tab completion logic to command classes and fix duplicates

61483dd

Co-authored-by: dmccoystephenson <[email protected]>

Remove redundant isArchived check in ArchiveCommand tab completion

d1119c5

Co-authored-by: dmccoystephenson <[email protected]>

Copilot finished work on behalf of dmccoystephenson January 7, 2026 04:32

dmccoystephenson marked this pull request as ready for review January 7, 2026 04:49

dmccoystephenson merged commit 3561b95 into main Jan 7, 2026

		return options.stream()
		.filter(option -> option.toLowerCase().startsWith(input.toLowerCase()))

Add tab completion for commands and arguments #79

Add tab completion for commands and arguments #79

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